Question

Calculati :
2+4+6+8+.......+1000
(5 la puterea 3 ) la puterea 6

[37-(x-1) x 3] x 2 =14

Answer 1

$a).\displaystyle 2+4+6+8+...+1000=2(1+2+3+...+500)= \\ \\ =2 \times \frac{500(500+1)}{2} =2 \times \frac{500 \times 501}{2} =\not2 \times \frac{250500}{\not2} =250500 \\ \\ b).(5^3)^6=5^1^8 \\ \\ c).[37-(x-1) \cdot 3] \cdot 2=14 \\ (37-3x+3) \cdot 2=14 \\ (40-3x) \cdot 2=14 \\ 80-6x=14 \\ -6x=14-80 \\ -6x=-66 \\ x= \frac{-66}{-6} \\ x=11$